Short for floppy drive, high density, and pronounced fud-hud. FDHD refers to 3 -inch disk drives for Macintosh computers that can accept double-density or high-density 3 -inch floppy disks. FDHDs can also read DOS –formatted floppy disks, which enables Macintosh computers and PCs to share data. FDHD drives are often called SuperDrives.